1. Field of the Invention
The present invention relates to pharmaceutical compositions, kits and methods for preventing and treating reduced or imbalanced concentrations of sex steroids and conditions which can respond favorably to increased activity of androgens and/or estrogens. The invention utilizes androst-5-ene-3β, 17β-diol (hereinafter 5-DIOL) or compounds converted in vivo to 5-DIOL
2. Description of the Related Art
5-DIOL is a compound biosynthesized from DHEA through the action of reductive 17β-hydroxysteroid dehydrogenase (17β-HSD) and is a weak estrogen. It has an 85-fold lower affinity than 17β-estradiol (E2) for the estrogen receptor in rat anterior pituitary gland cytosol (Simard and Labrie, J. Steroid Biochem., 26: 539-546, 1987), further confirming the data obtained on the same parameter in human myometrial and breast cancer tissue (Kreitmann and Bayard, J. Steroid Biochem., 11: 1589-1595, 1979; Adams et al., Cancer Res., 41: 4720-4926, 1981; Poulin and Labrie, Cancer Res., 46: 4933-4937, 1986).
At concentrations well within the range of the plasma levels found in adult women, 5-DIOL enhances cell proliferation and progesterone receptor levels in human mammary tumor ZR-75-1 cells which lack 3β-hydroxysteroid dehydrogenase/D5-D4 isomerase activity (Poulin and Labrie, Cancer Res., 46: 4933-4937, 1986) and increases the estrogen-dependent synthesis of the 52 kDa glycoprotein in MFC-7 cells (Adams et al., Cancer Res., 41: 4720-4926, 1981).
In general, it is known that the serum levels of DHEA and DHEA-S decrease with age and correspondingly, that there is a dramatic reduction in the formation of androgens and estrogens in peripheral target tissues and a marked decrease in the biochemical and cellular functions induced by sex steroids. As a result, DHEA and DHEA-S have been used in the treatment of a variety of conditions which are associated with decrease and/or imbalances in the levels of sex steroids. Recently, we have found that the serum levels of 5-diol decrease markedly with age.
Osteoporosis, a condition which affects both men and women, is associated with a decrease in androgens and estrogens. Estrogens have been shown to decrease the rate of bone degradation while androgens have been shown to build bone mass.
Menopausal symptoms have also been associated with a loss of estrogens, and low dose estrogen therapy is commonly used in perimenopausal and menopausal women to relieve vasomotor symptoms, urogenital atrophy, irritability, sleep problems, loss of energy, osteoporosis, and other symptoms associated with menopause.
In addition, breast cancer, cardiovascular disease, and insulin resistance have been associated with decreased serum levels of DHEA and DHEA-S and both DHEA and DHEA-S have been suggested to prevent or treat these conditions. DHEA has also been suggested to have beneficial effects in the treatment and/or prevention of obesity, diabetes, atherosclerosis, chemically-induced breast, skin, and colon cancer, autoimmune diseases, Alzheimer's disease, loss of memory, aging and to support energy, muscle mass, and longevity. Uses of DHEA as well as the benefits of androgen and estrogen therapy are discussed in International Patent Publication WO 94/16709.
DHEA and DHEA-S have been suggested to be better for the treatment of these conditions than standard estrogen and androgen therapy since the action of DHEA and DHEA-S is targeted to the tissues which can convert DHEA and/or DHEA-S to specific sex steroids. However, high doses of DHEA are required to get the necessary estrogenic and androgenic effects. Most importantly, the androgenic effects of DHEA are predominant and therefore, for conditions in which a higher proportion of estrogens is desired or where androgenic side effects are a problem, especially in women, the present invention permits a better proportion of estrogenic versus androgenic effects.